Convert to using dict style key lookups in XenAPI
Convert to using dict style key lookups in XenAPI

Fixes bug 1030073

With instances being passed as dicts via the RPC API, uses of the instance
object should use dict style key lookups instead of attribute style
lookups.

Change-Id: Iefc0e403d440aada68b259ded457166ad10699fd

n0ano/gantt,n0ano/gantt